Vehicle door lock, shift lever interlock system

ABSTRACT

A put-in-park alarm which is energized whenever an automatic shift vehicle is stopped but the shift lever is not in park. The put-in-park alarm is energized when the driver moves his door handle in a door opening direction. Not only is the alarm energized but the door cannot be opened until the shift lever is moved to park whereupon the signal is deenergized, but the door is unlocked upon a second movement of the handle in a door opening direction. The invention includes a broken/maladjusted alarm which is different from the put-in-park alarm but produces substantially similar results.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to safety systems for automatic transmissionvehicles and more particularly to a system whose primary function is towarn a driver when he has stopped his vehicle but failed to place theshift lever in park, where "park" means "latched park" so that thevehicle is properly restrained. The system includes subsidiary safetyfeatures which will become apparent as the description proceeds.

2. Background of the Invention

The patent to Mochida, U.S. Pat. No. 4,482,885, is representative ofsystems which sound an alarm when a driver prepares to leave a vehiclewith the transmission selector lever not in park. There are priornumerous other examples, including applicant's own prior U.S. Pat. No.5,015,991, of alarms which are sounded when the driver is remiss inattending to matters affecting the safety of a vehicle presumably parkedin a non-lethal condition. For example, alarms are sounded to remind adriver to remove the keys, to set the emergency brake, to set thetransmission in park, etc., but in common with all of these is the factthat only alarms, visible and/or audible, are depended upon to remindthe driver to put matters to right before he leaves the vehicle. Theproblem with alarms alone is the fact that a driver becomes so used tothem that he simply ignores them. While in most instances, e.g. whenparking on a level street, ignoring an alarm may lead to no danger,there are occasions when this is not so, e.g., parking on a slope. Thusthere is a need for a system which does more than merely signal an alarmbut rather forcibly calls the attention of the driver to an alarm to putmatters to right before he is able to exit the vehicle.

The broad object, therefore, of the invention is to provide a system forautomatic transmission vehicles whose function is to sound alarmscalling attention to the oversight or to vehicle derangement while thedriver is forcibly reminded to give heed to the alarms before he is ableto exit the vehicle.

SUMMARY OF THE INVENTION

The invention comprises a lock bar for at least the driver's side doorwhich, as soon as the shift lever is moved to any position except park,is moved to lock the door. When the vehicle arrives at its destinationbut the driver neglects to move the shift lever to latched park, as soonas he tries to open the driver-side door by its handle an alarm issounded while the lock bar remains in its locking position thus forciblyreminding the driver that the shift lever is not in park. As soon as thelever is placed in latched park, the lock bar is shifted to anon-locking position and the driver is able to open the door by theusual latch operating system of conventional construction responsive tomovement of the door handle in a door opening direction.

The invention includes a second alarm responsive to a broken ormaladjusted shift linkage which permits the shift lever to be moved topark yet the linkage remains in its preset position not in park which isto say the linkage remains in any preset position except park. Underthese conditions the invention provides that the driver side doorremains locked while the broken/maladjustment alarm sounds. Because thedoor remains locked, the driver's attention is drawn to the second alarmwhereupon he is reminded to set the hand brake after which he may move anormally open emergency switch to closed position which completes acircuit to unlocking electromagnetic means which moves the lock bar toits unlocking position enabling the driver to leave the vehicle when heagain operates the door handle.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete appreciation of the invention and many of the attendantadvantages thereof will be readily obtained as the same becomes betterunderstood by reference to the following detailed description whenconsidered in connection with the accompanying drawings, wherein:

FIG. 1 is a highly schematic showing of the system of the inventionsuperimposed on a highly schematic showing of a conventional automaticshift arrangement; and

FIG. 2 is similar to FIG. 1 but showing an improvement.

DETAILED DESCRIPTION OF THE INVENTION

At the outset, because of the unusual number of switches, applicant hasapplied as reference characters the numerals 1 through 8 to switchesshown in FIG. 1 which are not readily distinguished from each byconventional terminology. As will be apparent there are more than eightswitches but the remainder are readily distinguishable by conventionalterminology. It is hoped that applicant's somewhat unusual procedure inconnection with switches 1 through 8 will be helpful to a reader andlessen possible confusion.

To proceed with the detailed description the numeral 10 designates asource of electric power and 12 designates manual controls which may besubstantially the same as in FIG. 1 of applicant's prior U.S. Pat. No.5,015,991. These controls are not relevant to the present invention. Theinvention is utilized in conjunction with a conventional shift levermovable between a latched park position and any one of a number of otherpositions except park.

The invention includes a door lock bar 20 for at least the driver's sidedoor (not shown), and for locking the door the bar is extended in thedirection of arrow 22 upon energization of locking electromagnetic means24, which may be a conventional solenoid coil. The bar is retracted in adoor unlocking direction, indicated by the arrow 26, upon energizationof unlocking electromagnetic means 28. The bar 20 is retained in eitherits lock or unlock position by a spring loaded detent 30.

First and second switches 1, 2 are connected in parallel between thesource of electrical power 10 and the locking and unlockingelectromagnetic means 24, 28, respectively, the switches being movableby the lock bar 20 between a first position enabling the lockingelectromagnetic means 24 to be energized, and the unlockingelectromagnetic means 28 to be deenergized, and vice-versa when the lockbar is moved to a second position.

Circuitry, broadly indicated by the numeral 32, extends between theunlocking electromagnetic means 28 and the second switch 2. Thecircuitry includes a third normally open switch 3 which is closed uponoperation of a driver's side door handle 34 in a door opening direction,and fourth and fifth switches 4, 5 connected in parallel. The unlockingelectromagnetic means 28 is connected in series with switch 4 the latterbeing closed only when the shift lever is in park.

The tang 54 or inner end of the shift lever mounted on the steeringcolumn is spring loaded to force the tang against the contact surface ofthe insert plate 56 normally associated with the steering column. Tang54 may instead be a detent of the type which restrains floor mountedshift levers, or the shift lever itself where the shift lever protrudesfrom an insert plate as the shift lever cover. More generally, the tang54 may instead be any spring loaded component or part of the shift leverwhich is latched in park slot 52 of the insert plate, as shown in FIG.1.

The conventionally spring loaded bridge carrying member 38 is in theupward position in all shift lever positions other than park and ismoved into in the downward position as the tang 54 enters park slot 52when the gear shift lever is in park (shown at 54') In the upperposition, bridges 4', 6' and 7' serve switches 4, 5, 6 and 7. When theshift lever is moved to park, the tang 54 is lowered by a spring (notshown) which forces the tang 54 against the stepped surfaces and intothe park slot 52 of the insert plate 56, thereby lowering bridgecarrying member 38. Bridges 4', 6' and 7' thus open switches 5, 6 and 7while bridge 4' is moved to the dotted line position of FIG. 1 to closeswitch 4, all for reasons which will become clear as the descriptionproceeds.

A put-in-park alarm 40 is connected in series with the fifth switch 5,the unlocking electromagnetic means 28 being energized to retract saiddoor lock bar 20 whenever the door handle 34 is moved in a door openingdirection to close switch 3 and the shift lever is in park so as toclose switch 4. It should be understood that when the door handle 34 ismoved in a door opening direction, the handle operates conventional doorlatching mechanism (not shown) so that the door is opened in the usualmanner. Should, however, the shift lever be in any position except parkit will be apparent in FIG. 1 that switch 4 is open and switch 5 isclosed. Now when the driver depresses the handle 34 the unlocking coil28 cannot be energized because switch 4 is now open and because switch 5is closed, when the driver moves the handle in a door opening directionto close switch 3 a circuit is completed to the put-in-park alarm 40 andbecause the door won't open, the driver's attention is attracted to thealarm signal and he will invariably place the shift lever in parkwhereupon the switch 4 is closed to complete the circuit to theunlocking electromagnetic means 28 and upon the next operation of thedoor handle 34 the lock bar 20 is retracted and the door opens in anormal manner.

Applicant deliberately has not arranged the system to retract the lockbar automatically upon movement of the shift lever to park but ratherthe driver must operate the door handle a second time to effectretraction of the bar. This is because there may be situations where itis highly desirable that the door remains locked even after the driverhas been reminded to move the lever to park. One such situation would bewhere there is a threatened car jacking.

Though the switch 6 has been alluded to, its function has not beendescribed. As is clear, switch 6 is in series with the lockingelectromagnetic means 24 and the switch is closed when the locking baris in its unlocking position. Thus when the shift lever is moved to anyposition except park the locking electromagnetic means 24 is energizedvia switches 1 and 6 and the bar moves to its locking position, openingswitch 1 and closing switch 2. When the shift lever is moved to park,switch 6 is opened and when the driver moves the handle 34 to open thedoor, the unlocking electromagnetic means 28 is energized throughswitches 2, 3, and 4. It will be noted that a double acting switch 42 isin series with switch 4 and the opening electromagnetic means 28. Duringnormal operation the switch 42 occupies the dotted line position andseldom interferes with normal operation of the system. The switch 42occupies the full line position upon movement of the shift lever to anyposition except park and also in response to a broken or maladjustedshift linkage even after the shift lever is moved to park as will beexplained in greater detail below.

The invention also includes an external alarm 44 directed to theexterior of the vehicle. The bridge-carrying member 38 carries a seventhswitch 7 which is closed when the shift lever is in any position exceptpark and is opened when the shift lever 14 is moved to park. A normallybiased-closed seat switch 46 is provided in series between said sourceof power and the switch 7, the seat switch 46 being opened in responseto the weight of a driver seated in a normal position for driving thevehicle. When the shift lever is in any position except park and switch7 is thereby closed, should the driver thereafter, for any reason, leavehis normal driving position, as for example, by sliding to the passengerside of the seat, the external alarm is energized primarily for thepurpose of warning by-standers that the vehicle may be in a dangerouscondition. As soon as the shift lever is moved to park, the switch 7 isopened and the external alarm is extinguished.

Referring to FIGS. 1 and 2, the invention includes a broken ormaladjusted linkage alarm 48 and a conventional shift linkage as shown,for example, in FIG. 1 of my prior U.S. Pat. No. 5,015,991. Thepreviously referred to double-acting switch 42 is connected by linkage89 to be movable in unison with an eighth switch 8 (described below ingreater detail) between a first dotted line position connecting thefourth switch 4 to the unlocking electromagnetic means 28 and a secondfull line position connecting the fourth switch 4 to thebroken/maladjusted linkage alarm 48 while disconnecting the unlockingelectromagnetic means 28 from the fourth switch 4. When the shift leveris moved to park but, due to a broken or maladjusted shift linkage thedouble acting switch 42 remains in its full line position connecting thebroken/maladjusted linkage alarm to switch 4. This is because it and theswitch 8 are located in a manner analogous to switch 81 in FIG. 1 of myprior U.S. Pat. No. 5,015,991, and respond to, e.g., the position of theroostercomb of the linkage.

In accordance with the invention, the eighth switch 8 is connectedbetween the seat switch 46 and the external alarm 44. When switch 8 isin its closed full line position (corresponding to a linkagemalfunction), the external alarm 44 is connected to the seat switch 46.When the shift lever is moved to park and the shift linkage isfunctioning normally, the switch 8 is moved to the dashed line openposition at the same time as the switches 7 and 42 are likewise opened.However, in the event of a broken or maladjusted linkage, the switch 8remains closed and thus the external alarm is energized as soon as thedriver leaves his normal driving position. Thus, as soon as the handle34 is operated in a door opening direction, the lock bar remains in itslocking position because both of the electromagnetic means 24, 28 aredisconnected from the power source, but the broken/maladjusted linkagealarm 48 is energized.

When there is a broken or maladjusted linkage it has been demonstratedthat the lock bar remains in its locking position. Because this could bedangerous under certain circumstances the invention includes a normallyopen, manually closeable switch 58 connected in series with the doubleacting switch 42 and is connected to circuit 32. The switch 58 isconnected to the unlocking electromagnetic means 28 whereby in anemergency an occupant of the vehicle can close the switch 58 and effectretraction of the lock bar 20 even though the double acting switch 42 isin its second, full line position and the shift lever is in park.

In accordance with the invention an armature 60 is fixed to door handleoperated switch 3. An electromagnetic coil 62 surrounds the armature 60and is connected to the put-in-park alarm 40 whereby when handleoperated switch 3 is closed, the switch 3 is retained closed and theput-in-park alarm 40 energized until the shift lever is put-in-park todeenergize the put-in-park alarm 40.

Another feature of the invention resides in elongating the armature 60carried by door operated switch 3 and surrounding the elongated armaturewith a second coil 64 which is connected to the broken/maladjustedlinkage alarm 48 and is continuously energized to retain switch 3 closedand alarm 48 energized.

Another feature of the invention is illustrated in FIG. 2 and comprisesan auxiliary circuit 66 which may be substituted for some circuitry ofFIG. 1, such as the switch 8 and the connection 89, or may be used inconjunction with all the circuitry of FIG. 1. A normally open auxiliaryswitch 68 in the circuit 66 has an operative connection 70 between thenormally open manually closeable emergency switch 58 whereby saidauxiliary switch 68 is moved in unison between its open and closedposition with emergency switch 58 and, when closed, effects energizationof the external alarm 44. The auxiliary switch may carry an armature 72surrounded by an electromagnetic coil 74 connected to the external alarm44 whereby when the normally open, manually closeable switch 58 isclosed in an emergency, both that switch 58 and the auxiliary switch 68are retained closed to energize the external alarm 44 so long as theauxiliary switch is maintained in its closed condition. The seat switch46 may be added to circuit 66 between switch 68 and alarm 54 so that theexternal alarm is not energized until the driver leaves his seat.

It is believed that the operation of the invention should be apparentfrom the foregoing. An important aspect of the invention resides in theall important feature of reminding the driver to put the shift lever inpark not only by the put-in-park alarm which is energized when the doorhandle 34 is moved in a door opening direction but by the inability ofthe door handle to open the door until the lever is placed in park. Thisis the root cause of many accidents some of which are fatal. Anothercause of serious accidents is accidental movement of a vehicle due tobroken or maladjusted shift linkage which can be especially dangerousbecause the shift lever has already been moved with accustomed ease intopark, though the linkage may be still in drive. Thus the invention, whenit senses such a condition, again prevents the door from being openedand at the same time energizes a second broken linkage alarm 48,distinctly different from the put-in-park alarm 40, to warn the driverthat he has a serious problem and that he must immediately apply hisparking brakes. Thereafter the driver may exit the vehicle by operationof the emergency normally open, manually closeable switch 58.

The external alarm warns the public that the vehicle is not in a safepark position if the driver hurriedly slides across the front seat andleaves by the passenger door or uses the auxiliary switch to open thedriver's door, ignoring the internal put-in-park and broken linkagealarms.

Obviously, numerous modifications and variations of the presentinvention are possible in light of the above teachings. It is thereforeto be understood that the invention may be practiced otherwise than asspecifically described herein.

I claim:
 1. Vehicle door lock shift lever interlock system comprising:asource of electrical power, a shift lever movable between park and anyposition except park, a door lock bar, locking electromagnetic means forextending said lock bar in a door locking direction, unlockingelectromagnetic means for retracting said lock bar in a door unlockingdirection, first and second switches connected in parallel between saidsource of electrical power and said locking and unlockingelectromagnetic means, respectively, said switches being movable by saidlock bar between a first position enabling said locking electromagneticmeans to be energized and said unlocking electromagnetic means to bedeenergized and vice versa, circuitry between said unlockingelectromagnetic means and said second switch, said circuitry including athird normally open switch closeable upon operation of a driver's sidedoor handle in a door opening direction, and fourth and fifth switchesconnected in parallel, wherein said unlocking electromagnetic means isconnected in series with said fourth switch which is closed only whensaid shift lever is in park, and a put-in-park alarm connected in serieswith said fifth switch which is closed whenever said shift lever is inany position except park, wherein said unlocking electromagnetic meansis energized to retract said door lock bar when said shift lever is inpark and said door handle is moved in a door opening direction, saidput-in-park alarm being energized but not said unlocking electromagneticmeans whenever said shift lever is in any position except park and saiddoor handle is moved in a door opening direction.
 2. The system of claim1 including a sixth switch in series with said locking electromagneticmeans which is open to prevent energization of said lockingelectromagnetic means when said shift lever is in park and closed toeffect energization of said locking electromagnetic means when saidshift lever is in any position except park.
 3. The system of claim 2including an external alarm directed to the exterior of said vehicle, aseventh switch which is closed when said shift lever is in any positionexcept park and opened when said shift lever is in park, a normallybiased closed seat switch in series between said source of power andsaid seventh switch, said seat switch being opened in response to theweight of a driver seated in a normal position for driving the vehicle,said external alarm being energized when said shift lever is in anyposition except park so that said seventh switch is closed and thedriver thereafter, for any reason, leaves his normal driving position,whereby said seat switch automatically closes.
 4. Vehicle door lockshift lever interlock system comprising:a source of electrical power, ashift lever movable between park and any position except park, a doorlock bar, locking electromagnetic means for extending said lock bar in adoor locking direction, unlocking electromagnetic means for retractingsaid lock bar in a door unlocking direction, first and second switchesconnected in parallel between said source of electrical power and saidlocking and unlocking electromagnetic means, respectively, said switchesbeing movable by said lock bar between a first position enabling saidlocking electromagnetic means to be energized and said unlockingelectromagnetic means to be deenergized and vice versa, circuitrybetween said unlocking electromagnetic means and said second switch,said circuitry including a third normally open switch closeable uponoperation of a driver's side door handle in a door opening direction,and fourth and fifth switches connected in parallel, wherein saidunlocking electromagnetic means is connected in series with said fourthswitch which is closed only when said shift lever is in park, and aput-in-park alarm connected in series with said fifth switch which isclosed whenever said shift lever is in any position except park, whereinsaid unlocking electromagnetic means is energized to retract said doorlock bar when said shift lever is in park and said door handle is movedin a door opening direction, said put-in-park alarm being energized butnot said unlocking electromagnetic means whenever said shift lever is inany position except park and said door handle is moved in a door openingdirection; a broken or maladjusted linkage alarm, a shift linkagecontrolled by said shift lever, a double acting switch movable between afirst position connecting said fourth switch to said unlockingelectromagnetic means and a second position connecting said fourthswitch to said broken/maladjusted linkage alarm while disconnecting saidunlocking electromagnetic means from said fourth switch, and means formoving said double acting switch to said second position and preventingsaid double acting switch from moving to said first position when saidlinkage is not functioning normally.
 5. The system of claim 4 includingan external alarm directed to the exterior of said vehicle, a normallyclosed seat switch in the driver's position and being moved to openposition by the driver's weight, said seat switch being connected tosaid power source, and an eighth switch linked to said double actingswitch and connected between said seat switch and said external alarm,said eighth switch such that said external alarm is energized wheneverthe driver for any reason moves from his normal driving positionresulting in closure of said seat switch.
 6. The system of claim 4including a normally open, manually closable switch connected in serieswith said double acting switch and parallel to said broken/maladjustedlinkage alarm, said manually closable switch being connected to saidunlocking electromagnetic means whereby in an emergency an occupant ofthe vehicle can close said switch and effect retraction of the lock bareven though said double acting switch is in its second position and saidshift lever is in park.
 7. The system of claim 1 including an armatureon the third door handle operated switch, a electromagnetic coilsurrounding said armature and connected to said put-in-park alarmwhereby said third switch is retained closed until said shift lever ismoved to park and said fifth switch is opened to deenergize saidput-in-park alarm and said electromagnetic coil is deenergized.
 8. Thesystem of claim 4 including an armature on the third door handleoperated switch, an electromagnetic coil surrounding said armature andconnected to said broken/maladjusted linkage alarm whereby said thirdswitch is retained closed so long as the broken/maladjusted linkagealarm is energized.
 9. The system of claim 6 including an auxiliarycircuit connecting said external alarm to said power source, a normallyclosed seat switch in said circuit.
 10. The system of claim 6 includingan external alarm and a normally open auxiliary switch connected inseries between said source of electrical power and said external alarm,wherein said normally open auxiliary switch is operatively connectedwith said normally open manually closable switch such that said normallyopen auxiliary switch and said normally open manually closable switchmove in unison.
 11. The system of claim 10 including a seat switchconnected in series with said normally open auxiliary switch. 12.Vehicle door lock shift lever interlock system comprising:a source ofpower, a shift lever movable between park and any position except park,a door lock bar, locking means for extending said lock bar in a doorlocking direction, unlocking means for retracting said lock bar in adoor unlocking direction, first and second switches connected inparallel between said source of power and said locking and unlockingmeans, respectively, said switches being movable between a firstposition enabling said locking means to be energized by said source ofpower and said unlocking means to be deenergized from said source ofpower and vice versa, circuitry between said unlocking means and saidsecond switch, said circuitry including a third normally open switchcloseable upon operation of a driver's side door handle in a dooropening direction, and fourth and fifth switches connected in parallel,wherein said unlocking means is connected in series with said fourthswitch which is closed only when said shift lever is in park, and aput-in-park alarm connected in series with said fifth switch which isclosed whenever said shift lever is in any position except park, whereinsaid unlocking means is energized to retract said door lock bar whensaid shift lever is in park and said door handle is moved in a dooropening direction, said put-in-park alarm being energized but not saidunlocking means whenever said shift lever is in any position except parkand said door handle is moved in a door opening direction.
 13. Thesystem of claim 12 including a sixth switch in series with said lockingmeans which is open to prevent energization of said locking means whensaid shift lever is in park and closed to effect energization of saidlocking means when said shift lever is in any position except park. 14.The system of claim 13 including an external alarm directed to theexterior of said vehicle, a seventh switch which is closed when saidshift lever is in any position except park and opened when said shiftlever is in park, a normally biased closed seat switch in series betweensaid source of power and said seventh switch, said seat switch beingopened in response to the weight of a driver seated in a normal positionfor driving the vehicle, said external alarm being energized when saidshift lever is in any position except park so that said seventh switchis closed and the driver thereafter, for any reason, leaves his normaldriving position, whereby said seat switch automatically closes.
 15. Thesystem of claim 12 including:a broken or maladjusted linkage alarm, ashift linkage controlled by said shift lever, a double acting switchmovable between a first position connecting said fourth switch to saidunlocking means and a second position connecting said fourth switch tosaid broken/maladjusted linkage alarm while disconnecting said unlockingmeans from said fourth switch, and means for moving said double actingswitch to said second position and preventing said double acting switchfrom moving to said first position when said linkage is not functioningnormally.
 16. The system of claim 15 including an external alarmdirected to the exterior of said vehicle, a normally closed seat switchin the driver's position and being moved to open position by thedriver's weight, said seat switch being connected to said power source,and an eighth switch linked to said double acting switch and connectedbetween said seat switch and said external alarm, said eighth switchsuch that said external alarm is energized whenever the driver for anyreason moves from his normal driving position resulting in closure ofsaid seat switch.
 17. The system of claim 16 including a normally open,manually closable switch connected in series with said double actingswitch and parallel to said broken/maladjusted linkage alarm, saidmanually closable switch being connected to said unlocking means wherebyin an emergency an occupant of the vehicle can close said switch andeffect retraction of the lock bar even though said double acting switchis in its second position and said shift lever is in park.
 18. Thesystem of claim 12 including means for retaining said third switchclosed until said shift lever is moved to park and said fifth switch isopened to deenergize said put-in-park alarm and release said means forretaining said third switch closed.
 19. The system of claim 12 includingan armature on the third door handle operated switch, a electromagneticcoil surrounding said armature and connected to said put-in-park alarmwhereby said-third switch is retained closed until said shift lever ismoved to park and said fifth switch is opened to deenergize saidput-in-park alarm and said electromagnetic coil is deenergized.
 20. Thesystem of claim 15 including a second means for retaining said thirdswitch closed so long as the broken/maladjusted linkage alarm isenergized.
 21. The system of claim 17 including an auxiliary circuitconnecting said external alarm to said power source, a normally closedseat switch in said circuit.
 22. The system of claim 17 including anexternal alarm and a normally open auxiliary switch connected in seriesbetween said power source and said external alarm, wherein said normallyopen auxiliary switch is operatively connected with said normally openmanually closable switch such that said normally open auxiliary switchand said normally open manually closable switch move in unison.
 23. Thesystem of claim 22 including a seat switch connected in series with saidnormally open auxiliary switch.